cache: clean root path (#2023)
cache: clean root path (#2023)

Trim "/" from the root path to fix "slice bounds out of range" panic
in cache.go:1272.

Fixes #1945
yonjah/rclone,yonjah/rclone,ncw/rclone,olihey/rclone,B4dM4n/rclone,olihey/rclone,ncw/rclone,olihey/rclone,olihey/rclone,seuffert/rclone,seuffert/rclone,yonjah/rclone,yonjah/rclone,seuffert/rclone,seuffert/rclone,B4dM4n/rclone,B4dM4n/rclone,ncw/rclone,B4dM4n/rclone,ncw/rclone